From the article:
"But the story doesn't stop there. Lawn and colleagues found that the introverts in their sample who were comfortable with their introversion
showed higher levels of authenticity than did those who wanted to be
more extraverted, and were able to achieve a level of well-being that
came close to the level experienced by extraverts. These findings
suggest that simply making a change in one's judgment about
one's placement on the extraversion-introversion continuum can have a profound effect on well-being and authenticity." [Bold is mine]
g:
The bold above holds for all people for self-acceptance.
The specific definition of introversion is interesting and together with the rest of the article makes me think the introvert/extrovert distinction is hugely overvalued.
In the article's view, happiness correlates mostly with self-acceptance and the negative experiences of "introverts" is due to societal definition moving them to the fringe. Again, this holds regardless of the reason you end up on the fringe.